Knife sheath



FIG. 1 is a perspective view of a knife sheath showing my new design;

FIG. 2 is a front elevational view,

FIG. 3 is a rear elevational view,

FIG. 4 is a left side elevational view,

FIG. 5 is a right side elevational view,

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken line showing is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for knife sheath, as shown and described. 